title: Pharmacokinetics and penetration of marbofloxacin from blood into the milk of cows and ewes.
abstract: The single-dose disposition kinetics of marbofloxacin were determined in lactating cows and ewes after intravenous (i.v.) and intramuscular (i.m.) administration of 2, 2.5 and 4 mg/kg. Drug concentrations in blood and milk were determined by microbiological assay and the data were subjected to compartmental and non-compartmental kinetic analyses. In cows, the i.v. serum elimination half-life (t1/2 beta) was approximately 2 h and the i.m. serum elimination half-life (t1/2el) was approximately 3 h. The mean steady-state volume of distribution (Vss) was 1.5 l/kg for the cows and 0.6 l/kg for the ewes. The i.m. availability was nearly 100% for both cows and ewes. Drug penetration into the milk was rapid and extensive with milk marbofloxacin concentrations exceeding those in serum 2 h after administration. Milk drug concentrations equal to or greater than the minimal inhibitory concentrations for the majority of gram-negative udder pathogens were maintained for approximately 12 h after i.v. and i.m. treatment of 2-4 mg/kg. The drug was not detected in milk 24 h after treatment (sensitivity limit of assay = 0.05 microgram/ml).
authors.affiliation: Ministry of Agriculture, Kimron Veterinary Institute, Bet Dagan, Israel.
authors.forename: M
authors.initials: M
authors.lastname: Shem-Tov
authors.forename: G
authors.initials: G
authors.lastname: Ziv
authors.forename: A
authors.initials: A
authors.lastname: Glickman
authors.forename: A
authors.initials: A
authors.lastname: Saran
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000032:analysis / Q000493:pharmacokinetics*; D002417:Cattle / Q000097:blood / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005260:Female; D024841:Fluoroquinolones; D006207:Half-Life; D007273:Injections, Intramuscular / Q000662:veterinary; D007275:Injections, Intravenous / Q000662:veterinary; D008892:Milk / Q000737:chemistry / Q000378:metabolism*; D015363:Quinolones / Q000008:administration & dosage / Q000032:analysis / Q000493:pharmacokinetics*; D012756:Sheep / Q000097:blood / Q000378:metabolism*; D013997:Time Factors
chemical_list: D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D015363:Quinolones; C080260:marbofloxacin